Kubuntu 15.04 no sound on HDMI (Intel NUC D54250WYK)

There are similar questions and good answers on this forum. Unfortunately none of them addresses my problem.

I had perfectly well functioning sound system on the Kubuntu 14.10 on same hardware, but for number of reasons I decided to upgrade to 15.04. It was complete install (and not muon upgrade).

My situation is slightly different:

• all sound devices are showing:

tad@tad-desktop:~$ aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: HDMI [HDA Intel HDMI], device 3: HDMI 0 [HDMI 0]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 0: HDMI [HDA Intel HDMI], device 7: HDMI 1 [HDMI 1]
  Subdevices: 1/1

  Subdevice #0: subdevice #0
card 1: PCH [HDA Intel PCH], device 0: ALC283 Analog [ALC283 Analog]
  Subdevices: 1/1
  Subdevice #0: subdevice #0

• Hardware revs (lspci -v) :

00:03.0 Audio device: Intel Corporation Haswell-ULT HD Audio Controller (rev 09)
    Subsystem: Intel Corporation Device 2054
    Flags: bus master, fast devsel, latency 0, IRQ 46
    Memory at f7c34000 (64-bit, non-prefetchable) [size=16K]
    Capabilities: 
    Kernel driver in use: snd_hda_intel
00:1b.0 Audio device: Intel Corporation 8 Series HD Audio Controller (rev 04)
    Subsystem: Intel Corporation Device 2054
    Flags: bus master, fast devsel, latency 0, IRQ 45

    Memory at f7c30000 (64-bit, non-prefetchable) [size=16K]
    Capabilities: 
    Kernel driver in use: snd_hda_intel

Card: HDA Intel HDMI                      F1:  Help                                                                             
Chip: Intel Haswell HDMI                  F2:  System information                                                             

View: F3:[Playback] F4: Capture  F5: All  F6:  Select sound card                                                
Item: S/PDIF                              Esc: Exit                                                                           

• Speaker test terminal output (no sound):

tad@tad-desktop:~$ speaker-test -Dplug:hdmi

speaker-test 1.0.28

Playback device is plug:hdmi
Stream parameters are 48000Hz, S16_LE, 1 channels
Using 16 octaves of pink noise
Rate set to 48000Hz (requested 48000Hz)
Buffer size range from 64 to 16384
Period size range from 32 to 8192
Using max buffer size 16384
Periods = 4

was set period_size = 4096
was set buffer_size = 16384
 0 - Front Left
Time per period = 2.645183
 0 - Front Left
...

Any other suggestions from the community?

...So far no answer :-(

I have question to @nitzanms : what version of the kernel solved your No sound over HDMI running 15.04 on NUC D54250WYK ?

I am not sure what was a culprit but I wanted to share my story. Bottom line is - the sound system is working now. There were numerous system updates via Muon including update of the kernel to 3.19.0-31-generic since my original post in mid October.

Also there are two HDMI hardware devices on INTEL NUC:

$ aplay -l

**** List of PLAYBACK Hardware Devices ****
card 0: HDMI [HDA Intel HDMI], device 3: HDMI 0 [HDMI 0]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 0: HDMI [HDA Intel HDMI], device 7: HDMI 1 [HDMI 1]
  Subdevices: 1/1
  Subdevice #0: subdevice #0

I suspect one is corresponding to HDMI output and other to DP.

Late in October, I made fresh install of Kubuntu 15.10 on the same hardware and the sound system worked immediately. I also noticed that kernel changed to 4.2.0-16-generic.